JP2952751B2 - Organic electrolyte battery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electrolyte battery used under high pressure such as in the deep sea.

[0002]

2. Description of the Related Art As a battery used under high pressure in the deep sea or the like, there are a lead storage battery and a silver oxide-zinc battery using an aqueous electrolyte. These batteries are charged under atmospheric pressure, and are used as a power supply for measuring instruments and a power supply for driving an underwater vehicle under high pressure such as deep sea.

Such a battery is disclosed in Japanese Patent Application Laid-Open Nos. 49-85530 and 49-85531 by the same applicant as the present application.
Issue. As shown in FIG. 1, an outline of an open-type cell 16 having an aqueous electrolyte solution in a sealed space formed by a battery storage tank 11 and a pressure equalizer 13 (an expansion / contraction body made of a rubber bag or the like). And the insulating oil 9 are accommodated, and are designed to equalize a plurality of unit cells in a lump.
In this figure, a seawater introduction hole for introducing seawater to the outer peripheral portion of the pressure equalizing device 13 is omitted.

[0004] However, batteries using the above-mentioned aqueous electrolyte have drawbacks such as low energy density and short charge / discharge cycle life.

To overcome the drawbacks of a deep-sea battery using such an aqueous electrolyte solution, and to provide a battery having a large energy density and a long charge-discharge cycle life, Japanese Patent Application Laid-Open No. 2-139850 is also available. No. 4,098,045, there is an organic electrolyte battery for deep sea. This deep-sea organic electrolyte battery includes a positive electrode, a negative electrode made of lithium or a lithium alloy, and an organic electrolyte, and is provided with a pressure equalizer. This is shown in FIG. In this figure,
Reference numeral 1 denotes a unit cell tank, 2 denotes a power generating element, 4 and 5 denote positive and negative terminals, 8 denotes an electrolytic solution, and 13 denotes a rubber bag pressure equalizing device.

[0006]

However, in the case of the deep-sea organic electrolyte battery disclosed herein, the power generation element and the electrolyte are housed in a single cell tank, and the pressure balance is controlled by the electrolysis in the pressure equalizer. Since the structure is maintained by moving and shrinking the liquid, there is a problem that a pressure equalizer is required for each cell.
(When a plurality of cells are stored, they become a common electrolyte and a problem of current leakage occurs between the cells.) Further, in an organic electrolyte battery, what is important is how to eliminate the adverse effect of moisture. Considering the countermeasures against the moisture in the insulating oil in the case of the conventional aqueous electrolyte battery shown in FIG. 1 and the moisture penetrating through the pressure equalizer in the case of the above-mentioned deep-sea organic electrolyte battery, Not at all.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has as its object to simplify the structure, have a large energy density, is not affected by moisture, and has a charge / discharge cycle. It is an object of the present invention to provide an organic electrolyte battery having a long life and a pressure equalizing device.

[0008]

In view of the above, a battery storage tank provided with a pressure equalizing device, a plurality of organic electrolyte cells contained in the battery storage tank, and a space filled in the battery storage tank are filled. An insulating liquid having a specific gravity smaller than that of the organic electrolyte, and having an interface between the insulating liquid and the organic electrolyte always in the cell; in the organic electrolyte battery, in the battery storage tank or in the cell; Alternatively, an organic electrolyte battery having a moisture adsorbent in both, especially an organic electrolyte unit cell, has a buffer tank for pressure equalization, and the interface between the insulating solution and the organic electrolyte is always in the buffer tank for pressure equalization, so that The conventional problem is solved by the organic electrolyte battery, wherein the agent is disposed in the buffer tank for equalizing pressure.

[0009]

The inventors of the present application have investigated the cause of the case where such a conventional organic electrolyte battery may not exhibit the expected performance. And found that it was adversely affected by moisture that gradually entered through insulating oil.

Therefore, as a result of various investigations, the above configuration was adopted to prevent the water in the insulating oil or the water entering through the pressure equalizing device under the deep sea from reaching the organic electrolytic solution, so that the structure was improved. The present inventors have found that it is possible to provide an organic electrolyte battery which is simple, has a high energy density, is not affected by moisture even in use in the deep sea or the like, and has a long charge / discharge cycle life, and has completed the present invention.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments.

FIG. 3 is a diagram showing a cross section of a unit cell 17 having an organic electrolyte according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a unit cell tank, and reference numeral 2 denotes a power generation element including a positive electrode, a negative electrode, and a separator. 3 is a battery cover,
The battery case 1 is hermetically fixed by laser welding.
4 is a positive terminal and 5 is a negative terminal. Positive and negative terminals 4, 5
Are fixed to the battery lid 3 by a hermetic seal made of glass 6 as an insulating member. In this embodiment, the battery case 1, the battery cover 3, and the positive and negative terminals 4, 5 are made of stainless steel.

Reference numeral 7 denotes an electrolyte buffer tank mounted on the upper part of the battery case. The lower part communicates with the inside of the cell and the upper part communicates with the outside through a porous body (not shown). ing. Reference numeral 8 denotes an electrolytic solution filled in the single cell tank and the buffer tank. 9 is an insulating liquid described later.

Reference numeral 10 denotes an interface in the buffer tank between the electrolytic solution 8 and the insulating liquid 9 made of liquid paraffin. The interface 10 does not exceed the upper surface of the buffer tank 7 under normal pressure and does not exceed the upper surface of the power generating element 2 under high pressure equivalent to deep sea. It is set not to fall below. This is because if the interface 10 exceeds the upper surface of the buffer tank 7, the electrolyte may overflow and cause a short circuit between the cells, and if the interface 10 is lower than the upper surface of the power generating element 2, the power generating element is contaminated with the insulating liquid. This is because battery performance may be degraded. In addition, the cell tank 1 and the buffer tank 7 are in communication,
Since the space can be regarded as substantially the same space, the interface 10 in the buffer tank 7 is also regarded as “the interface in the unit cell”.

Reference numeral 18 (black dots in the buffer tank 7) denotes a molecular sieve for adsorbing moisture. In this example, the buffer tank 7 is filled. The moisture adsorbent may be disposed in the internal space of the battery storage tank partitioned by the equalizing device described later. However, by filling the buffer tank 7, the moisture can be more efficiently and reliably removed by the organic electrolysis. It is possible to prevent intrusion into the liquid cell. Needless to say, it is more effective to fill both the inside of the buffer tank 7 and the inside of the battery storage tank.

The organic electrolyte unit cell in this embodiment is:
A battery having a capacity of 10 Ah using LiCoO ₂ as a positive electrode, carbon capable of storing and releasing lithium ions as a negative electrode, and a solution obtained by dissolving 1 mol LiPF ₆ in a mixed solution of ethylene carbonate and diethyl carbonate as an electrolytic solution. It is.

FIG. 4 is a diagram showing an example of the organic electrolyte battery according to the present invention. In FIG. 4, reference numeral 11 denotes a battery storage tank, and reference numeral 14 denotes a seawater introduction hole that connects the inside and the outside of the battery storage tank. Reference numeral 13 denotes a rubber film-like pressure equalizing device that divides the internal space and the external space of the battery storage tank 11, and that connects the internal space and the external space of the battery storage tank 11 partitioned by the pressure equalizing device 13. This is for equalizing the pressure.

Reference numeral 17 denotes the unit cells shown in FIG. 3, and four cells are stored in the internal space of the battery storage tank 11 partitioned by the equalizing device 13. Reference numeral 9 denotes an insulating liquid filled in the internal space of the battery storage tank 11 partitioned by the pressure equalizing device 13, and reference numeral 15 denotes a pressure equalizing hole formed in a wall disposed in the space.

When the organic electrolyte battery is settled into the deep sea (sedimentation / raising means is not shown), seawater is generated due to a pressure difference between the inside and outside of the battery storage tank 11 partitioned by the pressure equalizing device 13. Penetrates into the battery storage tank 11 through the seawater introduction hole 14, presses the pressure equalizing device 13 downward in the drawing, and the insulating liquid 9 moves toward the unit cell group through the pressure equalizing hole 15. As a result, the insulating liquid 9 penetrates into the buffer tank through the porous body provided on the upper part of the buffer tank 7 of the unit cell, and the inside and outside of the unit cell are kept at a uniform pressure. Battery The battery is not damaged or deformed.

When this organic electrolyte battery is floated from the deep sea, the inside and outside of the unit cell are maintained at a uniform pressure by the reverse mechanism.

The point to be noted in the present invention is how to eliminate the adverse effect of the moisture in the insulating solution or the moisture penetrating through the equalizing device on the organic electrolyte. As a means for achieving this, a moisture adsorbent is provided in the battery storage tank and / or the unit cell. It is also an essential requirement to select an insulating solution having a specific gravity lower than that of the organic electrolyte and a property of being incompatible with the organic electrolyte.

The above-mentioned organic electrolyte battery was immersed in simulated seawater and allowed to stand for 10 days under a pressure of 1000 atm.
Simulated a 10,000 meter sea floor atmosphere. The amount of self-discharge for 10 days was 3% or less, which was not different from the amount of self-discharge under normal pressure. After the standing test, a 50-cycle charge / discharge test was performed.
Percent. It was the same as the capacity decrease under normal pressure.

[0023]

As described above, the organic electrolyte battery according to the present invention comprises a battery storage tank provided with a pressure equalizing device, a plurality of organic electrolyte cells contained in the battery storage tank, and a battery storage tank. In the organic electrolyte battery, which is an insulating solution filled in the space portion and has a specific gravity smaller than that of the organic electrolytic solution, and the interface between the insulating solution and the organic electrolytic solution is always in the unit cell. Provide a moisture adsorbent in the battery storage tank and / or the unit cell.Especially, the organic electrolyte unit cell has a buffer tank for equalizing, and the interface between the insulating solution and the organic electrolyte is always in the buffer tank for equalizing. The organic electrolyte battery according to the present invention is characterized in that the moisture adsorbent is disposed in the buffer tank for pressure equalization. To Adverse effects are effectively eliminated. Accordingly, it is possible to provide an organic electrolyte battery having a simple pressure equalizing device having a long charge / discharge cycle life, a high energy density, and a simple structure even under a high pressure such as deep sea, which is easily affected by water.

[Brief description of the drawings]

FIG. 1 is a diagram showing a conventional technique.

FIG. 2 is a diagram showing a conventional technique.

FIG. 3 is a view showing a unit cell having an organic electrolytic solution according to one embodiment of the present invention.

FIG. 4 is a view showing an organic electrolyte battery according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Single cell tank 2 Power generation element 3 Battery lid 4 Positive electrode terminal 5 Negative terminal 6 Glass insulating member 7 Buffer tank 8 Electrolyte 9 Insulating liquid 10 Electrolyte-insulating liquid interface 11 Battery storage tank 13 Pressure equalizer 14 Seawater introduction hole 15 Equalizing hole 16 Single cell 17 Single cell 18 Moisture adsorbent

Claims (2)

(57) [Claims] 1. A battery storage tank provided with a pressure equalizing device, a plurality of organic electrolyte cells stored in the battery storage tank, and an insulating liquid filled in a space in the battery storage tank. The organic adsorbent has a specific gravity lower than that of the electrolyte, and the interface between the insulating liquid and the organic electrolyte is always in the cell. An organic electrolyte battery comprising: 2. An organic electrolyte unit cell includes a buffer tank for pressure equalization, an interface between the insulating solution and the organic electrolyte is always in the buffer tank for pressure equalization, and a moisture adsorbent is disposed in the buffer tank for pressure equalization. The organic electrolyte battery according to claim 1, wherein: